How to Set the Length of Time for an IP Lease

I have been given responsibility for the guest Internet connections in the hotel at which I work. The problem is that over the last summer, we ran out of IP addresses at the end of July and into early August - the peak of our season.

Our guest access is controlled by Small Business Server 2003. I've gone into the DHCP settings and set the lease time to 6 hours, but the leases are still 8 days long. If anyone can help, I'd appreciate it. The access is through both wired and wireless connections. We found that in addition to laptops, our guests were connecting through smart phones, game consoles and tablets. Sometimes as many as 6 devices in a room.

SBS 2003 (small business server) has built-in limitation of 75 users/devices. So, the first issue is whether that number is routinely exceeded. If so, you find a better solution which matches the capacity, requirements of your network.
By default, the cleanup cycle occurs every 60 minutes. You can adjust the duration of the default grace period after which an expired lease is marked for deletion by editing the following key in the registry:

Before assuming this issue is DHCP related, you might want to look into the available licenses issue. If you exceed available licenses (this is especially a potential problem when experience rapid turnover in devices and do not scavenge addresses fast enough to return them to the available pool for reassignment). Check Application log.
The following error is also recorded in the Application event log:
"No license was available for user Domain\Username using product Productname. Use Licensing from the Administrative Tools folder to ensure that you have sufficient licenses."
You can manually scavenge IP addresses/licenses. You can also purchase additional license through MS or your local service provider/consultant.
The Premium version of SBS can have as many as 250-300 users.

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What IP range that you are currently using.
If you are running out of IP addresses then it's better to create subnets or migrate the IP address class. For eg. If you are using class C then shift to class B, if you are using class B then shift to class A network.

Have you tried changing the IP in SBS 2003? It's not easy. In fact, short of a clean install, it's next to impossible. We use 192.168.32.0 as our subnet. The guests only use a device for a about an hour, turn on another device, turn it off, use another device, etc. Since the time connecting is so short, it would be more efficient to shorten the lease. I've set the lease time to 36000 seconds; but the time of lease hasn't changed. I'm interested in returning addresses to the pool quicker.

I have to work within the confines of hotel policy. The only Linux boxes in the hotel are TIVO's and my laptop. I appreciate the suggestion, but all I need to know is what's keeping the lease time at 8 days.

SBS 2003 (small business server) has built-in limitation of 75 users/devices. So, the first issue is whether that number is routinely exceeded. If so, you find a better solution which matches the capacity, requirements of your network.
By default, the cleanup cycle occurs every 60 minutes. You can adjust the duration of the default grace period after which an expired lease is marked for deletion by editing the following key in the registry:

Before assuming this issue is DHCP related, you might want to look into the available licenses issue. If you exceed available licenses (this is especially a potential problem when experience rapid turnover in devices and do not scavenge addresses fast enough to return them to the available pool for reassignment). Check Application log.
The following error is also recorded in the Application event log:
"No license was available for user Domain\Username using product Productname. Use Licensing from the Administrative Tools folder to ensure that you have sufficient licenses."
You can manually scavenge IP addresses/licenses. You can also purchase additional license through MS or your local service provider/consultant.
The Premium version of SBS can have as many as 250-300 users.

I salute you for offering an appropriate, measured non-hostile reply. For some Linux evangelists', no matter what the situation they seem to have a need to interject that installing Linux is the universal cure.

I suspect that sooner or later, at the site of a horrific accident on I-5, someone will ask if there is a Dr. in the crowd ? some Linux apostle will suggest - "put Linux on that compound fracture, that'll fix it"!

I do not believe you can have 250-300 users with SBS. It comes with 5 CALs and you can only add up to 25 CALs with standard edition if it is SBS 2003.
What is the number of CALs purchased for the SBS server?
How is your network configured? What is the physical area you are trying to cover?
I would offer a suggestion that your connect a router between the SBS server and the modem or what ever you use to connect to the internet. Use the router to allow guest access. This would keep the guest off of the hotel network, where they do no need to be anyway from a security point of view.

This is where the linux suggestion came from - SBS is a poor tool to use for guest access. A separate network with a more robust (and flexible) solution for providing addresses and security would be more appropriate from a usability and security perspective. Your options are roll your own with a free/affordable tool (Linux or Unix), Windows or a hardware solution that is optimized to do exactly what you need. IE, an affordable firewall appliance. Anything from a cheap linksys firewall router to an expensive enterprise model from Watchguard, Cisco, Fortinet, etc.

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